The Morpho Didius of the Nymphalidae Family
by Wordlet
Summary: In which Luffy knows a lot more about bugs then he used to and Sabo wants to know why.


**AN: Please note, all scientific** **statements** **are factual and there is a glossary at the end of the fic should you get confused. Thank you for reading!**

 **Also, Happy New Year ;)**

 **Disclaimer: I do not own One Piece**

 ***A LINE BREAK… BEHOLD***

"…And the _Morpho didius_ was so pretty! A perfect specimen of the _Nymphalidae_ family, the species is actually quite rare on a seasonal range island like this..." Luffy lamented, kicking his feet in the air, leaning back to look at the sky through the leaves of the forest canopy. "And Mingo just sliced right through it! I haven't seen one in years!"

"Seen what again?" Sabo yawned, reclined against the trunk of the tree, a few branches below Luffy.

" _Morpho didius."_ Luffy repeated heatedly, spinning his hat in his hands, agitated. "The Blue Morpho butterfly, most common to heated summer islands and a member of the _Nymphalidae_ family, one of the many families under the general term of the _Rhopalocera_ species _."_ He rattled off the information and thrust his hat back onto his head, looking down at Sabo, only for his attention to catch on the hairy yellow flowers that were blooming from the tree trunk, just beneath the branch his brother was lounging on.

Sabo blinks himself fully awake, pushing himself up out of his slouch and burping, then craning his neck to look up through the branches at his little brother. "Did you just tell me something in Latin?"

"Yeah." Luffy answered shortly, before reconsidering his answer. "It's the correct way to refer to an insect, so that's the language I usually talk about them with." Luffy cocked his head. "What's wrong with Latin?"

"Nothing! Absolutely nothing is wrong with Latin." Sabo yelped, suddenly nervous that he'd seemed averse to his brother's sudden interest in the language. "But, I don't remember you having any interest in Latin. Or English, actually."

"But I like bugs."

"I know that Luffy, you love bugs." Sabo rolled his eyes. That was an understatement. Luffy would do anything to have a few minutes to inspect a bug, and one of the most common reasons for him to wander off was to chase some flying insect he got distracted by and wanted to follow.

"You used to look for books about them for me." Luffy looked back up at the sky and, from the way the light shaded his eyes with his hat, the movement almost seemed planned to separate Sabo from his brother's thoughts. He frowned, wondering where he was going right now.

"I did." He admitted, "I think they were the only thing you let me teach you anything about." And he had tried _many_ different subjects.

"Nah. Fighting." Luffy corrected, dropping down from his branch to land on Sabo's. "Ne, let's go catch another boar, I'm hungry again." He dropped down to the forest floor, peering around eagerly, as though there would be a boar there, waiting for him to kill it.

"Hold on, we're still talking about bugs." Sabo leaped down next to him and adjusted his pipe on his back. "Why again are you so interested in knowing their scientific names? Aren't regular names plenty?"

"No!" Luffy laughed. "The more I know about bugs the cooler they are. I wish we found better books back then. I had to go steal them myself." He stretched his arm back up to the branch and pulled down his own pipe that he'd improvised for their hunting trip. "And you were a better teacher than any of those stuffy professors the books quoted." He stuck out his tongue and marched on into the foliage; Sabo blinking at one of the newest revelations about his brother.

"I think the extent of my lessons just touched the difference between moths and butterflies." He joked, pushing aside a large flower bloom to follow his brother into the denser bush of the jungle.

"Not even." Luffy replied "You told me that butterflies came out in the day, and moths were…" He paused, trying to fit his mouth around the word, which Sabo marveled at seeing as how he was getting through Latin just fine, "Nocturnal! But some butterflies _are_ nocturnal, and a couple of moths come out at dusk and dawn, which makes them partially diurnal. The easiest difference is that _Rhopalocera_ doesn't have fuzzy antennae, all moths have either fuzzy or saw-edged antennae. Here." Luffy crouched suddenly, and stared hard at one of the huge flowers that peppered Green Bit. Hesitating, Sabo knelt too, and watched the green flower for a moment. No denying it was pretty to look at but it was a flower, still. Vivid, electric, green with black stripes and dots peppered over the petals. Luffy pursed his lips and breathed out a puff of air just large enough to send the flower swaying, and a butterfly fluttered to life, a wingspan at least seven inches long and the same green and black pattern as the flower. It rose, wings beating effortlessly, and glided upward. Luffy stretched out his fingers and caught the humongous insect in his hands. It didn't seem to mind being caged, settling on his finger and moving its wings in and out slowly.

"See, no fuzz. This is an _Ornithoptera priamus poseidon,_ a Green Birdwing, of the _Papilionidae_ family. Specifically the _Poseidon_ subset. It's one of the largest species in the world, the biggest is _Ornithoptera alexandrae,_ that's Queen Alexandra's Birdwing. It's in the same family as this one." Sabo leaned in close, and took in the colors and size of the Birdwing, the green was an emerald, and the black deep and glowing. Luffy unclasped his fingers and the butterfly lifted into the air, pulling itself through the air and up into the forest canopy.

They stood there for a moment before Luffy squealed with delight, dropping onto his stomach, nose pressed to the ground, eyes following something moving along the ground. Sabo peered over his brother's hat, and almost flinched away from the creature Luffy was ogling.

"What the heck is that?"

" _Trachelophorus giraffe_ from the _Curculionidae_ family. Usually only found in very hot climates, with extremely moist conditions."

"It's weird."

"It's so cool!" He watched the beetle trundle over a stick in its path, and then begin scaling a leafy plant that really shouldn't be able to support the pink scaly coconuts that grew at the pinnacle of the thin stem.

"Why is its neck so long? Wait, is that its neck?"

"Yeah, it's long cause it's called the Giraffe Weevil."

"Things are named after what they look like: things are not made to look like what their names are."

"Eh? Then why is my name Luffy?" Luffy looks genuinely confused at the idea and Sabo mirrors the expression because he doesn't have a clue where the thought came from in the first place.

"Now what are you talking about?"

"Nami calls me a-luf, that's why I'm named Luffy, right?"

"Uh, I don't think so?" Sabo can't be sure. Dragon has the strangest tendencies at times, and it isn't totally unbelievable that he would name his kid after what he wanted him to become. Why anyone would actually call Luffy aloof (who was sitting there, moaning about the death of a butterfly) was a little beyond him. Luffy was not "cool and distant".

"Oh." Luffy looked puzzled but he turned back to the giraffe weevil and continued admiring the red shell and the sheen of its hard armor.

"What does it use its neck for? It seems like a hindrance to me." Sabo said finally, watching the weevil scuttle up the plant towards the denser leaves.

"Fighting." Luffy answered. "To get a mate, a male has to battle other males who also want the female. The long neck works kind of like swords against swords." He craned his own neck upwards, rather than rising with the beetle as it ascended the plant. Once it reached one of the outward reaching leaves, another weevil crawled from around the other side of the stalk and for a moment the two grappled and hooked their necks together. Sabo considered the benefits of having a hard, long neck: one wouldn't have to worry about their throat being slit, but using it as a weapon would put your face right in the middle of it, susceptible to slashes and blows.

"See, if we waited around for them to finish, there's probably a female hiding around here somewhere that they're fighting over. But I'm hungry, so let's go get something to eat!"

Luffy tugged on Sabo's coat sleeve and started walking, leaving his hand grasping Sabo's wrist, and his arm stretched across the distance between them. Sabo wasn't worried until Luffy ducked between a pair of trees and disappeared from sight, which consequently meant that his arm was going to get wrapped around things and tangled. They really didn't need a repeat of _That Particular Incident_ , especially not when he'd just gotten back to his little brother… On that train of thought, Sabo wrapped his own fingers around Luffy's wrist and hurried to follow through the place where his brother had disappeared. It took him a minute, (Luffy had managed to wind himself into some complicated knots in the process of finding a boar, and Sabo had had to untangle him as he walked) but Sabo soon returned Luffy's arm to its rightful length and Luffy grinned at him, peering out through bushes at a juicy looking boar. He'd been uncharacteristically patient and waited for Sabo to catch up before springing onto the innocent creature. The hunt today was a far cry from what they'd once accomplished in a day on Goa. The animals were no longer any semblance of a training challenge, and they barely fed the pair. But Sabo couldn't say he minded that; they had a full dinner waiting back on his ship, and the palace would provide Luffy with any number of full course meals as thanks for defeating Doflamingo, they'd be fine.

Sabo had a new goal.

"Hey Luffy, don't a lot of butterfly species travel in groups?"

"They're called Kaleidoscopes."

"What are called Kaleidoscopes?"

"Groups of butterflies."

"Oh."

Luffy shot him a happy look, proud that he had been able to correct _Sabo_ on something. Sabo was proud too.

"So, don't they travel in Kaleidoscopes?"

"Most families do." Luffy acknowledged thoughtfully, and suddenly sucked in a hasty breath. "If there was one _morpho didius_ then there may be thousands others from the same Kaleidoscope!" He's getting excited and Sabo nods along with the train of thought. Perhaps now Luffy wouldn't be so distressed over Doflamingo's dastardly deed of killing the blue butterfly.

"They would be in danger!" Luffy suddenly wailed. "This is a Spring Island during summer, it _snows_ here! They'd never make it through the winter!" He spun and seized Sabo by his arms. "We _have_ to do something."

You know, or maybe he would get more distressed.

"Okay, what do you want to do about it?"

"Move them. They have to leave this island. And… And before they lay their eggs! Or else a whole other generation will be here to freeze!" Luffy had an I-can't-let-that-happen look on his face and Sabo put a hand on his shoulder to still the panicking boy.

"Hey, calm down. We can do that. Let's find a summer island somewhere around, nice and tropical. And Law can get them all at once, he'd be willing, right? His devil fruit powers could have them all in a cage on my ship in a few seconds."

"Yeah…" Luffy thinks it over slowly, looking into the space over Sabo's shoulder as though it's happening behind them, the butterflies being gathered up by flashing blue domes and taken to a safer, warmer place. The idea is starting to appeal. No matter how many Latin names Luffy knows Sabo can still read him like a book at most times, he can see Luffy deciding whether it would work. "Yeah! Traffy'd do it! Let's find him. Now!" Sabo snatched Luffy's shoulder to keep him from charging off in a random direction to find the surgeon.

"Hold on, let's find the kaleidoscope first." He suggested and Luffy nodded. He stretched his free arm upward and snagged on a branch high above.

"They'll be sunbathing!"

He shot upwards and Sabo grabbed him around the waist so they'd stay together. Only a few seconds later they burst through the tree canopy, drifting to a stop high above the tallest tree on Green Bit. He can see the far shore of Dressrosa, the smoke still coiling from some of the burned buildings. Green Bit itself is far from untouched, but the damage made by the meteors is behind them, and all he can see of the island from here is a lush jungle paradise of greens and tropical birds. It only takes a moment for both of their gazes to zero in on the kaleidoscope.

"There!" Luffy pointed out towards the edge of the island. A shimmering sheet of blue blanketed the treetops there. Sabo was struck breathless for a moment. It moved, alive with the soft fluttering of thousands of butterfly wings. His arms were wrapped around Luffy's waist and one of Luffy's arms had swung down to wrap around his own chest, to keep them together.

Then they fell back and they hit the ground in a burst of dust and tangled limbs.

"Ah! I don't know where they are!" Luffy yelped, standing up, his arms stretching from the shoulders even though his forearms were still wrapped around Sabo.

"East from here." Sabo told him, carefully unwinding one of the stretched limbs. "Why don't I dial Law and we'll get him to meet us there?"

" _Yes."_ Luffy said earnestly, dropping down beside Sabo to hug him. "Yes. That is exactly what needs to happen."

Sabo blinked, unhesitatingly hugging Luffy back as he slowly processed the situation.

"Luffy, is there something you're not telling me?"

"No, but there is something I wanna show you." He answers and steps back. He pulls Sabo to his feet and looks around for a moment before starting off in a seemingly random direction. There's no particular thing that Sabo notices about this way they are traveling but Luffy keeps going till pricker bushes start to pull at the cloth of his pants. There's a stream somewhere in the area and it's sunny, a gap in the tree canopy over top of them.

"Luffy…"

"Look!" Luffy hushes him and points to a bunch of nettles clumped around a tree trunk.

"What are we looking at…?" Luffy slaps a hand across Sabo's mouth and continues staring. Sabo laughs softly, because this is more Luffy-esque behavior then the urgent tone of his voice and the abrupt desperate hug. And the Latin. Definitely more Luffy then the Latin.

"Look _closely."_ Luffy stresses and Sabo squints to meet his insistence.

And there _is_ something there. A group of butterflies, still, their wings folded so that the outsides, looking like tree bark, are visible and not the inside.

" _Polygonia faunus hylas._ The Angel Wing butterfly." Luffy smiles. "Ace's butterfly."

Sabo holds his breath. Actually sucks in and forgets to breathe for a moment.

 _Ace's butterfly._

The idea is so right that the momentary shock of hearing his name is the only thing inconceivable about the moment. Luffy stands after a few seconds and steps softly over to the tree. He reaches in with a finger extended, the mass of butterflies flutter and one lights upon his finger, now Sabo sees the vibrant orange hue of the inside of the butterfly's wings. Orange with white and black spots. It's tiny, but that's ok. The edges of the wings are jagged, but the points have been smoothed so that they're more like knobs and dips. It is Ace to a tee.

"When I started really looking into butterflies, I found a few that reminded me of people." Luffy sat down next to where Sabo was crouched, careful to keep his hand steady. "The _Papilio palinurus_ is Makino's butterfly, the Emerald Swallowtail. Dadan is a _Vanessa cardui,_ a Painted Lady. Ace is _Polygonia faunus hylas._ " He lifts his finger closer to Sabo's eyes, gently shoving the butterfly into his face (an oxymoron only Luffy is capable of achieving.) "His used to be _… Vanessa atalanta,_ the Red Admiral… I changed it. He's an Angel Wing now."

"That sounds right."

And it did. There was nothing but perfection in the idea.

"Sabo's butterfly is _Morpho didius."_ Luffy says softly and Sabo starts. _Morpho didius_ was his butterfly. He thought again to the bright shimmering blanket of blue that flashed and breathed over that area of the tree tops. _"We_ have _to do something."_ Luffy had wailed. " _Yes. That is exactly what needs to happen."_ He had whispered.

They both sit for a moment and watch the Angel Wing fan its wings slowly open and closed. And Sabo chuckled softly.

"You're not worried about his butterflies, are they cold hardy?"

"Yeah. They hibernate."

He laughed and looked away for a moment. He was the tropical beauty, fragile and pretty. Ace was the adaptable, camouflaged, angel. Of course Luffy hadn't meant anything by it, he never would, but Sabo felt it nevertheless.

"Sabo. I chose the _Morpho didius_ because of its coloring, its brightness and its sunny habitat. The camouflage on the ventral wings hardly helps conceal it at all." Luffy cut into his thoughts, "They're always glistening. I love Sabo. His butterfly is really common in East Blue, it lives everywhere on Goa. I saw it every day." Sabo swallowed a sob and smiled wobbly.

"Right, let's give Trafalgar a call and get this show on the road." Sabo stood up slowly, so as not to scare the Angel Wing, and Luffy followed his movements, nodding at his words. "You have a crew to catch up with and an alliance to carry out, right?"

"Mm Traffy doesn't know what he's doing anymore. I messed up his plans." Sabo laughed and fished around in his pockets for the Den Den.

"You do that a lot Lu, don't sweat it."

 ***A LINE BREAK… BEHOLD***

"Is that all of them Luffy-ya?"

"I dunno. Probably. Kaleidoscopes rarely break up, and on a small island like this _Morpho didius_ would'nt have the space to expand into a second kaleidoscope. They're multivoltine, but that would have been months ago, so there are likely no chrysalises or caterpillars…" Law shook his head as Luffy rattled off some more rationalizations, he'd never understand Luffy-ya. He had thought he might, one day, but this revealed a whole new layer, and who knows, there might be more layers after that. Better to stop trying now.

"I'm going back to the ship, I was supposed to be meeting up with my crew days ago." Law reminded Luffy, a tinge of annoyance in his tone. He dropped his hand and the Room he'd had prepared snapped away as he hefted his nodachi onto his shoulder.

"And _you_ have missions piling up." Koala snapped at Sabo from where she'd been standing on the edge of the clearing. As Sabo's unofficial chaperone she'd tagged along with Law to rendevoux with Sabo, who had given her the slip for the morning. At the reminder of the duties he'd been pushing aside, the man winced.

"What's first?"

"Classified." Koala glanced meaningfully at Luffy who was peering under some plants, making sure there were no eggs lain on the underside of leaves.

"Oh please. I mean what kind of island." Sabo rolled his eyes. Koala could be such a stickler for protocol sometimes.

"Summer. Never gets below ninety degrees Fahrenheit."

"Lu, my next island never drops below ninety degrees Fahrenheit, sound good for the morphos?"

"Is there a jungle? Lots of flowers and fruit?" They both glanced at Koala and she nodded. "Then yeah!"

"Great." Koala smiled sternly at Sabo. "So, we'll get headed that way by sunset, right?"

After a slight hesitation Sabo nodded. Both he and Luffy had places they needed to go, they weren't little kids with time for lessons anymore, they were learning through doing things. They had to go their separate ways, no matter how much he dreaded watching his little brother's ride carry him over a different horizon then the one which he himself is sailing to. Luffy too deflated at the thought of separation. But he didn't protest, instead hooking one arm around Sabo's elbow and dragging him off toward the thicker parts of the jungle.

"Let's see if we can find a tiger, Sabo! One more hunt before next time!"

"Alright Lu, I'm coming." He glanced back at Koala and she waved him off with a pretend nonchalant wave. _Go, see if I care. When Dragon starts breathing down your neck, don't come whining to me… Like last time._

"Sabo! _Latrodectus mactans!"_ Luffy cried excitedly, diving into some foliage. Sabo chuckled and stepped into the shade himself.

"What kind of bug is that?" He humored him half expecting some kind of beetle, half expecting some foot wide butterfly.

"A Black Widow spider!"

...

" _Luffy!"_

 **AN: SO yeah. This fic was… Difficult, I won't deny it. I'm not entirely sure where the idea stemmed from. I know why I chose bugs though. One of my first experience with One Piece is of the Ultimate Red game. My friend got it for her birthday, and she started playing it after her party ended, but I was still around. At one point she was catching a bug, and I was like, why is that even a feature of the game? She told me that "Luffy is a bug geek". I saw enough of that game to get me interested in the plot and she'd been asking me to watch it anyhow, so I got into watching One Piece myself. (So happy I did)**

 **Though bugs are a minor part of the actual show, I've developed a head canon that Luffy adores bugs to no end, and actually knows a lot about them, thanks to this first experience (and Bugs by roseveare). Sabo was the one who wanted his brothers to learn things, and I figured, if he couldn't force the traditional subjects, then he'd probably stray to more interesting subjects. After he left, Luffy wanted to keep the feeling of Sabo around, so he continued his lessons. Hence, this fic. Granted, Luffy is more interested in beetles than butterflies, but I'm not Luffy, and butterflies were easier to use for symbolism, so there you go.**

 **BEFORE I FORGET EVERYONE THANK MY BETA FOR THIS STORY, CRAZYRUBSOFF. I've been trying to up my grammar checks because I know I annoyed some people in previous stories with my lack of grammatical comprehension. Thus, I have not only spell checked this, grammar checked this, and proofread it at least fifteen times (I'm serious, I've reread this fic so many times…) But I ALSO had my Mother proofread it, AND crazyrubsoff read through it and gave me still more corrections (both grammatical and writing wise). Hopefully, it's as shiny as a new print hardcover by this point. If not, then I think I'm hopeless.**

 **Next up is ye old glossary. I've included anything I could think of that wouldn't be clear, and some things that would be. Please know that all facts listed in this fic are indeed facts (as far as I know, Wikipedia and museum sites are my cited sources). Anymore questions or just curious, please review or PM! I've done of a lot of research, and I know where to go for answers!**

 **GLOSSARY**

 _ **Morpho didius:**_ **Blue Morpho butterfly, the one with the iridescent blue on its wings.**

 _ **Nymphalidae:**_ **a family of butterfly (fun fact, the Blue morpho and Angel Wing are both in this family)**

 _ **Rhopalocera**_ **: Butterfly**

 **Diurnal: only awake during the day, the opposite of nocturnal**

 _ **Ornithoptera priamus poseidon:**_ **Green Birdwing of the** _ **Poseidon**_ **subspecies**

 _ **Papilionida:**_ **a family of butterfly**

 _ **Ornithoptera alexandrae:**_ **Queen Alexandra's Birdwing, the largest butterfly in the world and a relative of** _ **Ornithoptera priamus Poseidon**_ **(fun fact, the average wing span of the Queen Alexandra's Birdwing is 25 cm or 9.5 inches while the Poseidon subspecies averages around 20 cm, that is, 7.8 inches.)**

 _ **Trachelophorus giraffe:**_ **A species of weevil with a long neck and a red armored shell, about the size of a lady bug**

 _ **Curculionidae:**_ **a** **family of beetle**

 **Aloof: (from ) 1. at a distance, especially in feeling or interest; apart: 2. reserved or reticent; indifferent; disinterested:**

 **Kaleidoscope: a group of butterflies OR a tube filled with different colored fragments that reflect off mirrors inside the tube and refract light through the fragments**

 _ **Polygonia faunus hylas:**_ **The Angel Wing butterfly**

 _ **Papilio palinurus:**_ **the Emerald Swallowtail (Makino's butterfly)**

 _ **Vanessa cardui:**_ **a Painted Lady butterfly (Dadan's butterfly)**

 _ **Vanessa atalanta:**_ **the Red Admiral butterfly (Ace's first butterfly)**

 **Ventral: The outside of the wings, the part you see when a butterfly puts its wings together (fun fact, the other side of the wings is called dorsal)**

 **Multivoltine: a species of butterfly with more than two generations of eggs laid per year (univoltine is one generation per year, divoltine is two generations per year)**

 _ **Latrodectus mactans:**_ **Black Widow spider, highly poisonous, though it's bite is generally not fatal. (Female bites are more dangerous than male bites, but the difference between the two is not discernible immediately)**


End file.
